中国医用诊断X射线工作者1950～1995年恶性肿瘤危险分析

目的：提供职业照射诱发人类恶性肿瘤的证据和评价其危害。方法：用O／E程序分析了我国24省、直辖市、自治区1950－1980年间在职的27011名医用诊断X射线工作者和25782名其他科医务工作人员1950－1995年间的恶性肿瘤发病资料。结果：X射线工作者的恶性肿瘤发病率明显高于对照医务人员，相对危险（RR）为1．2，95％可信限（CI）为1．1－1．3。发病率明显增加的肿瘤是白血病，皮肤癌，女性乳腺癌，肺癌，肝癌，膀胱癌和食管癌，RR分别为：2．2，4．1，1．3，1．2，1．2，1．8和2．7，甲状腺癌的发病率也见增加，R＝1．6，95％（CI）为0．9－2．6，结论：X射线工作者白血病、皮肤癌，女性乳腺癌，可能还有甲状腺癌相对危险的增高与职业X射线的照射有关，当累积剂量达到一定水平时，这些肿瘤的相对危险明显增高。

Risk analysis of malignant tumor among medical diagnostic X-ray workers in China,1950-1995

Objective To provide evidence of human malignant tumors induced by occupational exposure to ionizing radiation and to assess the resultant cancer risk. Methods Cancer incidence (1950-1995) among 27 011 medical X|ray workers was compared by means of O/E system with that of 25 782 other medical specialists employed between 1950 and 1980 in China. Results Significant cancer risk was seen among medical X|ray workers (RR=1 2,95% CI:1 1-1 3).Significantly elevated risks were found for leukemia and cancer of skin,female breast,lung,liver,bladder and esophangus,the RRs were 2 2,4 1,1 3,1 2,1 2,1 8 and 2 7,respectively.The RR of thyroid cancer also elevated but was not significant (RR=1 6,95% CI:0 9-2 6).The patterns of risk associated with number of years engaging in X|ray work,age,the calendar year of initial employment,and cumulative dose,suggesting that the excesses of leukemia,skin cancer,female breast cancer,and possibly thyroid cancer,were related to occupational exposure to X|rays. Conclusion These findings suggest that a significant cancer risk can be associated with occupational exposure to ionizing radiation when the cumulative dose reaches a certain level.